以13-氢过氧化-顺-9,反-11-十八碳二烯酸(HPODE)代表脂质氢过氧化物,研究脂质氢过氧化物氧化修饰对大豆蛋白凝胶性质的影响,采用质构仪、流变仪、持水性测定以及扫描电镜等方法表征大豆蛋白的凝胶性质。结果发现:蛋白质氧化造成大豆蛋白的凝胶硬度、凝胶形成温度、凝胶强度以及凝胶持水性,随着大豆蛋白氧化程度的增加,大豆蛋白凝胶的粗糙度增加,内部空隙变大,并且分布不均匀。蛋白质氧化对大豆蛋白凝胶性质的影响与HPODE浓度有关,当HPODE浓度低于0.1mmol/L时,蛋白质氧化对大豆蛋白凝胶性质的影响很小,可以忽略。

13-hydroperoxy-9Z,11E-octadecadienoic acid(HPODE) was selected as a representative of lipid hydroperoxide to investigate effects of oxidative modification by lipid hydroperoxide on the gel properties of soy protein.The soy protein was characterized by large deformation measurements,dynamic rheological measurements,water-holding capacity measurements and scanning electron microscopy.The results indicated that protein oxidation caused the decrease of gel hardness,gel formation temperature,gel strength and gel water-holding capacity of soy protein,and increase of the protein coarseness and interstice of the gel network,and uneven distribution of soy protein.Effects of protein oxidation on soy protein gel properties were related to HPODE concentration.Low concentration of HPODE(less than 0.1mmol/L) had no significant impact and can be ignored.